The technology relates to a semiconductor laser device having a mesa section, and also to a photoelectric converter and an optical information processing unit each having the semiconductor laser device.
In recent years, as microprocessor units (MPUs) have become more sophisticated in functionality, the amount of data transmitted and received among semiconductor chips such as large scale integration (LSI) has greatly increased. Thus, speed enhancement and capacity enlargement of signal transmission have been strongly desired. As a way of realizing these, optical transmission coupling technology (optical interconnection) in which electric signals are converted into optical signals and transmitted has been attracting attention (for example, see “Encounter with Optical Interconnection”, Nikkei Electronics, Dec. 3, 2001, pages 122 to 125, FIGS. 4 to 7, and also, see “Trends in Optical Interconnection Technology and their Impact on Next-Generation Equipment Packaging”, Yasuhiro Ando, NTT R&D, Vol. 48, No. 3, pages 271 to 280 (1999)).
In the optical transmission coupling technology (optical interconnection), a light-emission device (e.g., a surface-emitting semiconductor laser device) and a photodetector (e.g., a photodiode) are provided on a printed circuit board, and optical signals are transmitted through an optical waveguide (see Japanese Unexamined Patent Application Publication Nos. 2005-181610, 2006-237428, and 2006-258835, for example).
This surface-emitting semiconductor laser (vertical cavity surface emitting laser (VCSEL)) device serving as the light-emission device has, for example, an n-side electrode, a lower distributed bragg reflector (DBR) layer, an active layer, an upper DBR layer, and a p-side electrode in this order from a substrate side. Further, a mesa section is provided in a part of the surface-emitting semiconductor laser. This mesa section is embedded in an insulating layer made of resin. In other words, a top surface of such a laminated body is flat, which enables flip-chip assembly (see, for example, Japanese Unexamined Patent Application Publication No. 2010-141087).